Nematocidal haloalkyl acid ester



3,0s4n94 NEMATOCHDAL HALOALKYL ACID ESTER Samuel I. Ger-tier,Washington, D.C., dedicated to the public Filed ca. 4, 1955, Ser. No.538,537 8 Claims. ((11.167-22) (Granted under Title 35, US. Code (1952),sec. 266) No Drawing.

tion in the patent to be granted on this application are dedicated tothe public.

This invention relates to nematocides, their preparation and theirmethod of application. 1

Nematodes belong to a class of unsegmented worms of the phylumNemathelminthes. Certain species of this class of worm, members of thesubfamily Pratylenchinae are known to effect a number of subtropical andtropical plants. They have been found in the roots of citrus and a widevariety of other plants including many ornamentals. These rootinhibiting nematodes are believed to be responsible for spreadingdecline in citrus and cause millions of dollars of annual damage in theUnited States.

It has been found that esters of haloalkyl acids are effective agentsfor treating the roots of plants for the control of harmful nematodescontained therein.

These esters can be represented by the general formula R-(flJ-O R1wherein R is selected from a group consisting of GHi--, CH;(|JH- andurn-Cirrand wherein R is selected from a group comprising an alkylgroup, a halogen-substituted alkyl group, a cycloaliphatic group, analkyl-substituted cycloaliphatic group, an aralkyl group and anaroxyalkyl group.

The compounds were prepared by the esterification of the halogenatedacid with the required alcohol by methods known in the art, using asuitable catalyst, such as sulphuric acid or toluene-sulfonic acid.

The following examples illustrate the effectiveness of the compositionsmade according to this invention. Nematocide test compositions accordingto this invention contain from a minimum of 0.001 percent to 1.0 percentof eliective compound on a volume-volume basis in an aqueous mediumhaving dissolved therein from 2 to times as much of a Wetting agent,such as Triton X-lOO or Tergitol 4, by volume as the toxicant. Specifictest organisms were the golden nematode (Heterodera rostochiensis) andthe meadow nematode (Pratylenchus sp.).

EXAMPLE 1 Nematocide Tests Using Heterodera Rostochiensis Nematocidalemulsion compositions were prepared by treating an aqueous mixturecontaining from 0.001 to 1.0 percent by volume of the nematocide with0.005 to 5.0 percent of Triton X-lOO. 1A cyst mixture containing 100-300nematode cysts per test was dipped into the haloalkyl ester compositionfor periods from 1 to minutes. After removing from the toxicant thecysts were set aside and examined after a period of weeks and thepercentage of nonviable nematodes determined. The following table showsthe results on a number of representative compounds comprising thisgroup of haloalkyl esters.

TABLE I. NEMATOCIDAL ACTION OF HALOALKYL ESTERS AGAINST HeteroderaRostochiensis Percent Mortality of Nematodes Concentration, per- Name ofToxic Compound cent by Butyl chloroaeetate o o o co 0:0 8 S OH D04-Isopropylcyclohexyl pionate 2-Phenoxyethyl B-chloropropionate EXAMPLEII Nematocide Tests Using Pratylenchus sp.

For these tests the nematocidal emulsions were prepared as in Example Iusing concentrations of from 0.1 percent to 1.0 percent by 'volume.Ornamental plants such as azalea, philodendron, hibiscus, Chineseevergreen, midget palm and the like, the roots of which were infestedwith meadow nematode (Pratylenchus sp.) were used as a host. The rootsof these plants were washed free of adherent soil and the excess Waterremoved prior to treatment. The plants were then arranged in thetreating vessels so that only the roots were immersed in the nematocidalmedium for one hour. Splashing is avoided on the rest of the plant toprevent any possibility of injury to foliage. The plants are thenremoved, replanted in sterile soil and examined at daily intervals. Theroots were chopped in a Waring Blendor, the nematodes collooted bysieving and the efiectiveness of the control thus determined.

TABLE II.NEMATOCIDAL ACTION OF EALOALKYL ES- TERS AGAINST PRATYLENCHUSSP.

Concentra- Minimum, Name of Toxic Compound tlon, perpercent cent bycontrol volume Butyl chloroacetate 0.01 98 2-Isopropylcyolohexylchloroacetate 1. 0 -95 2-seo-Butylcyclohcxyl chloroaCetate. 1. 0 90-95Z-Chlorois opropyl 2-chlor0propionate. 1. 0 90-95 p-Methylcyelohexyl2-chloroproplonat 1. 0 90-95 Z-Chloroethyl ii-chloropropionate 0. 01 982-Methylpentyl 3-ch1oropropionote 1. 0 90-95 Z-Ootyl3-chloropropionate 1. 0 90-95 2-Ethylhexyl 3-chloropropionate. 1. 090-95 2-Buty1octyl 3-chloropropionate.. 1. 0 90-95 Benzyl3-chloropropionate 1. 0 90-95 Cyclohexyl 3-eh1oropropionate 1. 0 90-954-Isopropylcyclohexyl 3-chlor0pr0pionate 1. 0 90-95 Z-Phenoxyethyl3-chloropropionate 0. 1 98 These nematocidal compositions may be appliedto growing plants in the field by treating the soil around the roots.For this purpose the composition is applied in a suitable manner at therate of to 50 pounds of active ingredient per acre. The compositions mayalso be used in greenhouses.

I claim:

1. A method of preventing damage to plants by-nematodes which comprisescontacting the nematodes with a haloalkyl ester of the formula where Ris a radical selected from the group consisting of ClCH CHiCH- and ClCHCH and where R is a radical selected from the group consisting of alkyl,halogen substituted alkyl, cyclohexyl, alkyl-substituted cycloheXyl,benzyl, and phenoxyethyl, the hydrocarbon moiety of the radical Rcontaining from 2 to 12 carbon atoms.

2. The method of claim 1 wherein the haloalkyl ester is butylchloroacetate.

3. The method of claim 1 wherein-the haloalkyl ester is 2-chloroethyl3-chloropropionate.

4. The method of claim 1 wherein the haloalkyl ester is 2-phenoxyethyl3-chlor0propionate.

5. The method of claim l wherein the haloalkyl ester is2-isopropylcyclohexyl chloroacetate.

6. The method of claim l wherein the haloalkyl ester is benzyl3-chloropropionate.

7. A method of preventing damage to plants by nematodes which comprisesapplying to nematode-infested soil a haloalkyl ester of the-formulawhere R is a radical selected from the group consisting of C1CHr-3omenand ClCH -CH and where R is a radical selected from the groupconsisting of alkyl, halogen-substituted alkyl, c'yclohexyl,alkyl-substituted cyclohexyl, benzyl, and phenoxyethyl, the hydrocarbonmoiety of the radical R containing from 2 to 12 carbon atoms.

8. A method of preventing damage to plants by nema- 4 todes whichcomprises applying to nematode-infested roots of the plants a haloalkylester of the formula where R is a radical selected from the groupconsisting of ClCH GHQ-011- and ClCH -CH and where R is a radicalselected from the group consisting of alkyl, halogen-substituted alkyl,cyclohexyl, alkyl-substituted cyclohexyl, benzyl, and phenoxyethyl, thehydrocarbon moiety of the radical R containing from 2 to 12 carbonatoms.

References Cited in the file of this patent UNITED STATES PATENTS1,851,040 -Fikentscher et al Mar. 29, 1932 1,982,909 Flint Dec. 4, 19342,217,905 Hoffman Oct. 15, 1940 2,282,732 Lean May 12, 1942 2,377,446Payne June 5, 1945 2,415,251 Leavitt Feb. 4, 1947 2,422,728 Gresham eta1 June 24, 1947 2,430,326 Cheney Nov. 4, 1947 2,448,265 Kagy Aug. 31,1948 2,502,244 Carter Mar. 28, 1950 2,543,580 Kay Feb. .27, 19512,726,485 Thomas Dec. 13, 1955 2,730,547 Dye Jan. 10, 1956 2,770,638Giolito Nov. 13, 1956 2,779,680 Wolf Jan. 29, 1957 2,794,727 BarronsJune 4, 1957 2,802,021 Heininger Aug. 6, 1957 2,802,818 Wheeler Aug. 13,1957 2,802,831 Wheeler Aug. 13, 1957 2,809,983 Heininger Oct. 15, 1957OTHER REFERENCES Hiemenz et al.: J. Am. Chem. Soc. 71 (1949), pp.1137-8.

Roark et al.: 1nd. Eng. Chem. 20 (1928), pp. 512-3.

Websters New International Dictionary of the English Language, 2nd Ed.,1940, G. & C. Merriman & Co., p. 818.

King: US. Dept. Agr. Handbook No. 69, May 1954, pp. 29, 292.

1. A METHOD OF PREVENTING DAMAGE TO PLANTS BY NEMATODES WHICH COMPRISESCONTACTING THE NEMATODES WITH A HALOALKYL ESTER OF THE FORMULA